ASTRA-DESI Data Release 1 (DR1)

This record bundles the ASTRA-DESI DR1 products for the two DESI survey regions (NGC and SGC). Every catalogue is delivered as a compressed FITS binary table (.fits.gz) whose first extension (HDU 1) contains the data. File headers store the keywords RELEASE=DR1 and the corresponding ZONE label for quick checks.

Directory layout

The archive preserves the NERSC production tree. Top-level folders contain:

• raw/ – merged real and random catalogues per region.
• classification/ – neighbour count summaries per tracer and random iteration.
• probabilities/ – web-type membership probabilities derived from the classification counts.

Naming conventions

• raw/zone_REGION_TRACER.fits.gz – Region NGC or SGC.
• classification/TRACER/REGION/zone_REGION_TRACER_classified_iterXXX.fits.gz – combined tracer summary for the region.
• probabilities/TRACER/REGION/TRACER_REGION_TRACER_probability_iterdata.fits.gz – per-object web-type probabilities.
• properties/zone_REGION_properties.fits.gz – per-object properties.

Column reference

Raw catalogues (raw/*.fits.gz)

Properties catalogues (properties/*.fits.gz)

Each raw file merges all tracers for its zone. Random catalogues mirror the data counts for every tracer and random iteration. 

Additional columns SED_SFR, SED_MASS, FLUX_G, and FLUX_R were incorporated from the DESI DR1 value-added catalogues associated with the emission-line sample: https://data.desi.lbl.gov/doc/releases/dr1/vac/stellar-mass-emline/. These quantities are derived via SED fitting using CIGALE (Zou et al. 2024).

Classification catalogues (classification/*.fits.gz)

Probability catalogues (probabilities/*.fits.gz)

Using the catalogues

• All FITS tables are compressed with gzip.
• Random catalogues use RANDITER values 0–99; filtering on RANDITER >= 0 isolates the random iterations.
• The Cartesian coordinates assume the Planck18 cosmology provided by astropy.cosmology.Planck18.

• The masks are distributed as a compressed archive (masks.tar.gz) containing FITS maps with the following naming convention:

  • dr1_mask_{program}_nside{nside}_final.fits – binary mask defining the valid survey footprint for each program (bright or dark). Pixels with value 1 belong to the footprint, while 0 indicates excluded regions.
  • dr1_mask_{program}_nside{nside}_ngc.fits – mask restricted to the North Galactic Cap (NGC).
  • dr1_mask_{program}_nside{nside}_sgc.fits – mask restricted to the South Galactic Cap (SGC).

  Here, {program} corresponds to the DESI observing program (bright for BGS tracers and dark for LRG, ELG, and QSO), and {nside} indicates the HEALPix resolution parameter.

  For reproducibility, additional files are provided:

  • dr1_mask_{program}_nside{nside}_maps.npz – compressed NumPy archive containing intermediate maps used in the mask construction, including tile coverage, LSS object counts, and smoothed mask representations.